The manufacture of novelty yarns from combined ends is old in the art. Examples of novelty yarn involve combining untextured ends with no overfeed, one end being overfed at a rate greater than the other end; combining a falsetwist textured "core" yarn with a "flat" effect yarn; combining falsetwist textured "core" and "effect" yarns; among others.
U.S. Pat. No. 3,264,816 discloses a synthetic yarn wrapped with a staple fiber which is then combined with a core yarn.
U.S. Pat. No. 3,756,005 discloses a process for producing a novelty effect yarn by passing two yarns through a falsetwisting device and overfeeding one yarn into the falsetwist device with the use of an aspirator-type jet. The slubs formed along the core yarn are somewhat random in nature.
U.S. Pat. No. 3,474,613 discloses a novelty product made using an aspirating jet and a "slubbing" jet in combination in which the aspirating jet forces one end of yarn onto a foraminous surface, afterwards from which the textured yarn is combined with another yarn in the slubbing jet. The yarns are thereafter passed respectively through a tangling jet and a falsetwist jet.
U.S. Pat. No. 3,691,750 discloses a continuous filament falsetwist textured core yarn wrapped with another falsetwist textured yarn of higher crimp amplitude, the wrapper filaments forming reversing helices at intervals along the length of the core yarn.